The objects for which flickering was detected well above observational noise
are marked with an 'F' in the 'Flk' column of Table REF .
The detectability of flickering and its amplitude are usually dependent on
the actual epoch of observation [1]}. Orbital phases
with the hot spot in plain view are favoured (WD at quadrature moving toward
superior conjunction), while others can be detrimental, e.g. during
eclipses or passage at apoastron in a highly eccentric orbit (with
consequent reduction in mass transfer rate). Therefore, stars in
Table REF  that failed to show flickering at the single
epoch of our observation could do otherwise at a later revisit. This
is also the case for SU Lyn. When it was observed in late 2015 by Mk16 its
was in a high accretion state and it flickered wildly, while it was in a low
accretion state and did not flicker when [2]}
performed their observations in January 2018. Similarly, while large
amplitude flickering has always been the rule for MWC 560 (eg.
[3]}), it has disappeared altogether during the
last couple of years [4]}.
